Prevalence and associated factors of obstructive sleep apnea in refractory hypertension.

BACKGROUND: Refractory hypertension (RfHT) and obstructive sleep apnea (OSA) share common pathophysiological mechanisms and probably are intrinsically associated, but their prevalence, clinical profile, and polysomnography (PSG) pattern remain misunderstood. OBJECTIVE: To describe OSA prevalence and PSG pattern of patients with RfHT in a large cohort of resistant hypertension (RHT). METHODS: This is a cross-sectional study involving 418 RHT patients (30.9% male; mean age of 62.5 ±â€Š9.9 years) who were submitted to full-night PSG. RfHT was defined as uncontrolled ambulatory blood pressure monitoring using five or more antihypertensive drugs, including spironolactone. Bivariate analysis compared RHT and RfHT and multivariate analysis was performed to assess the independent correlates of OSA. RESULTS: A total of 90 patients (21.5%) were diagnosed with RfHT (26.7% male; mean age of 58.5 ±â€Š8.3 years). In comparison with resistant ones, RfHT patients were younger, with higher smoking and previous cardiovascular diseases prevalence, especially stroke. There was no difference regarding anthropometric measures. OSA prevalence (80.0 vs. 82.9%) and moderate/severe OSA (51.1 vs. 57.0%) were similar in both groups as well as apnea-hypopnea index. In its turn, refractory hypertensive patients presented better sleep efficiency (78 vs. 71%), with higher total sleep time (315 vs. 281 min) and lower sleep latency (11 vs. 17 min). There was no difference regarding rapid eye movement sleep, oxygen saturation, microarousals index, and periodic limb movement. CONCLUSION: In this large RHT cohort, resistant and refractory hypertensive patients have similar OSA prevalence, although refractory ones, which by definition use spironolactone, are younger and apparently have a better sleep pattern.

Characteristics and outcomes of autologous hematopoietic stem cell transplant recipients admitted to intensive care units: A multicenter study.

PURPOSE: Studies of critically ill hematopoietic stem cell transplantation (HSCT) recipients have mainly been single-center and focused on allogenic HSCT recipients. We aimed to describe a cohort of autologous HSCT with an unplanned intensive care unit (ICU) admission. METHODS: This study is a retrospective cohort study of autologous HSCT performed as a treatment for a hematological malignancy, during their first unplanned ICU admission in 50 hospitals in Brazil. We assessed the hospital mortality and the association between mechanical ventilation, vasopressors, and renal replacement therapy and hospital mortality in autologous HSCT recipients, adjusted for potential confounders. RESULTS: We included 301 patients. Multiple myeloma was the most common malignancy driving to HSCT. ICU and hospital mortality were 22.9% and 37.5%, respectively. After adjustment for potential confounders, mechanical ventilation (OR = 9.10; CI 95%, 4.82-17.15) was associated with hospital mortality, but vasopressors (OR = 1.43; CI 95%, 0.77-2.64) and renal replacement therapy (OR = 1.30; CI 95%, 0.63-2.66) were not. CONCLUSIONS: In this large cohort of critically ill autologous HSCT recipients, mechanical ventilation was the only organ support-therapy associated with increased mortality in autologous HSCT recipients.

Effects of continuous positive airway pressure treatment on aortic stiffness in patients with resistant hypertension and obstructive sleep apnea: A randomized controlled trial.

Resistant hypertension (RHT) is associated with obstructive sleep apnea (OSA) and increased aortic stiffness, measured by carotid-femoral pulse wave velocity (cf-PWV). We aimed to evaluate in a randomized controlled trial, the effect of Continuous positive airway pressure (CPAP) treatment on cf-PWV in comparison with a control group in patients with RHT and moderate-severe OSA. One-hundred and sixteen patients were randomized to 6-month CPAP treatment (56 patients) or no therapy (60 patients), while keeping their antihypertensive treatment unchanged. Carotid-femoral pulse wave velocity was performed at the beginning and end of the 6-month period. Intention-to-treat intergroup differences in cf-PWV changes were assessed by a generalized mixed-effects model with the allocation group as a fixed factor and adjusted for age, sex, changes in mean arterial pressure and the baseline cf-PWV values. Subgroup sensitivity analyses were performed, excluding patients with low CPAP adherence and low cf-PWV at baseline. CPAP and control groups had similar clinic-laboratorial characteristics. Patients had a mean cf-PWV of 9.4 ± 1.6 m/s and 33% presented cf-PWV > 10 m/s. During treatment, the control group had a mean increase in cf-PWV of +0.43 m/s (95% confidence interval [CI], +0.14 to +0.73 m/s; p = .005), whereas the CPAP group had a mean increase of +0.03 m/s (95% CI, -0.33 to +0.39 m/s; p = .87), resulting in a mean difference in changes between CPAP and control of -0.40 m/s (95% CI, -0.82 to +0.02 m/s; p = .059). Subgroup analyses did not change the results. In conclusion, a 6-month CPAP treatment did not reduce aortic stiffness, measured by cf-PWV, in patients with RHT and moderate/severe OSA, but treatment may prevent its progression, in contrast to no-CPAP therapy.

Correlates of aortic stiffness progression in patients with resistant hypertension: importance of clinic and ambulatory blood pressure changes.

OBJECTIVES: Correlates of serial aortic stiffness changes were scarcely evaluated. We aimed to evaluate them in patients with resistant hypertension, with particular attention to the importance of changes in clinic and ambulatory blood pressures (BP). METHODS: In a prospective study, two carotid-femoral pulse wave velocity (cf-PWV) measurements (three measures in each occasion) were performed with the Complior equipment in 442 resistant hypertensive patients over a mean follow-up of 4.6 years. Multivariable regressions assessed the independent correlates of changes in cf-PWV. All analyses were further adjusted for baseline cf-PWV and BP values, and for the time interval between measurements. RESULTS: Carotid-femoral PWV had a median increase of 0.11 m/s per year (1.1% per year). Overall, 224 patients (51%) had an increase or persisted with high cf-PWV, whereas 218 (49%) reduced or persisted with low values. On multivariable regressions, both changes in clinic SBP (partial correlation 0.34, P < 0.001) and in 24-h SBP (partial correlation 0.40, P < 0.001) were correlates of changes in cf-PWV. This means that the white-coat effect, defined as the difference between clinic and daytime BPs, affected cf-PWV changes (partial correlation 0.19, P < 0.001). The other independent correlates of aortic stiffness progression were older age, presence of diabetes, higher waist circumference and worse renal function. CONCLUSION: The exaggerated white-coat effect, by acutely increasing clinic BPs during cf-PWV examination, may partially obscure the beneficial effects of reducing ambulatory BP levels on aortic stiffness attenuation. Arterial stiffness measurements under ambulatory conditions may be needed to correctly assess aortic stiffness changes in resistant hypertensive patients.